Electric switch



April 22 1924.

w. LINDSAY ELECTRIC SWITCH Original Filed June 24 1922 2 Sheets-Sheet 1 April 22 1924. 1,491,152

- W. LINDSAY ELECTRIC SWITCH original Filed June 2 4, 1922 2 sheets-sheet 2 @zic/,6.

raam Apr. azfieza UNITED As'ra'rgzs PATENT OFFICE.

WILLIAM LINDSAY, OF CHICAGO, ILLINOIS, ASSIGNO'R TO HENRY HYMAN CO.,

INCORPORATED, OF NEW YORK, N. Y., A CORPORATION OF NEW YORK.

ELECTRIC SWITCH.

Application illed J'une 24., 1922, Serial No. 570,611. Renewed June 20, i923.

To a-ZZ t may concern.:

Be it known that I, WILLIAM LINDSAY, a citizen of the United States, residin in Chicago, in the county of Cook and tate of Illinois, have invented certain new and useful improvement in Electric Switches, of which the following is a specication.

This invention relates to that class of electric switch mechanisms in which a movable contact member or switch arm is operated by actuating means comprising a rotative reciprocatory spring pressed actuating member or plunger which is adapted to engage and operate such movable vcontact member or w switch arm to open and close an electric circuit.

The principal object of the invention is to provide a simple, economical and eici'ent electric switch mechanism.

A further object of the invention is to provide an economical and ecient electric switch mechanism or pull switch having a movable contact member or switch arm adapted to open and close an electric circuit, and having a rotative reciprocating actuating member or plunger in movable relation to and adapted to operatively engage and move the movable swltch arm into and out of circuit closing and circuit breaking 0 position in an efficient manner.

A further object is to provide such a switch with means for enabling the rotative longitudinally reciprocating plunger to be moved longitudinally in one direction by the action of the same spring which serves to return the plunger actuating ratchet mechanism to initial position after each operation of the plunger.

Other and further objects of the invention will appear from the following description and claims, and from an inspection of the accompanying drawings which are made a part hereof.

The invention consists in the features, combinations, details of construction, and arrangement of parts herein described and claimed.

In the accompanying drawings,

Figure 1 is a View in elevation of an improved electric switch constructed in accordance with my invention, showing the same mounted in a Y casing or receptacle which is shown in central longitudinal section, said switch mechanism being adapted for use as a canopy switch;

Fig. 2 is a view in horizontal section taken on line 2 2 of Fig. 1, looking in the direction indicated by the arrows, and shows the switch in circuit breaking position;

Flg. 3 isa view in central longitudinal section taken on line 3 3 of Fig. l looking in the direction indicated by the arrows;

Fig. 4 is a view Jin-central longitudinal section taken on line 4 4 of Fig. 2, looking in the direction indicated by the arrows, and shows the switch mechanism in circuit breaking position with the rotative longitudinally reciprocating plunger in initial positionor as it would appear at the moment of the completion of an operation of the movable contact member or switch-arm to circuit breaking position;

Fig. 5 is a similar view oil the mechanism shown in Fig; 4, showing the movable contact member or switch-arm in circuit breaking position, but with the rotative longitudinal reciprocating plunger in its retracted position, as it would appear at the moment of being released to move the movable contact member or switch-arm from circuit breaking to circuit closing position;

Fig. 6 is a similar view showing the parts illustrated in Figs. 4 and 5 in the positions which they would occupy upon the completion of the movement of the rotative longitudinally reciprocating actuating plunger from the position in which it is shown in Fig. 5 to the circuit breaking position in which it is shown in said Fig. 6;

Fig. 7 is a view in tranverse section taken on line 7 7 of Fig. 2 looking in the direction indicated by the arrows, and shows an end view of the inner or main frame in which the switch-arm and other movable parts of my improved switch mechanism are mounted;

Fig. 8 is a view in vertical section taken is, by preference, formed of a on line 8--8 of Fig. 2, looking in the direction indicated by the arrows and showing my improved electric switch as it would appear in end elevation with the ou-ter casing removed;

Fig. 9 is an enlar ed view of one of the sectional frame mem rs of the main frame of the Switch mechanism shown in Figs. 1 to 8, inclusive; n

Fig. 10 is a similar enlarged perspective view in det-ail of another section ormpart of a sectional frame, which is adapt to be rigidly connected with the frame member shown in Fig. 9;

` Fig. 11 is an enlarged detail view of a toothed ratchet member adapted to be operatively connected with the rotative longitudinally reciprocating actuating plunger, and with an actuating sprin for operating such ratchet member and p unger;

Fi 12 is an enlarged detail view in perspective of a metallic member of my improved movable contact member or switcharm, and is adapted to form an axle or pivot for the switch-arm;

Fig. 13 is an enlarged detail view in erspective of an insulating member of my improved movable switch-arm or contact;

Fig. 14 is an enlar ed detail view in perspective of the meta lic contact member of my improved switch-arm;

Fig. 15 is an enlarged detail view showing the actuating spring and pull chain for operating the rotative longitudinally reciprocating plunger and its actuating ratchet mechanism; and

Fig. 16 is an enlarged detail view in perspective of the rotative longitudinally reciprocating plunger for actuating the movable or pivoted switch-arm.

In constructing an improved electric switch mechanism in accordance with my invention, I provide a main frame 1, which lurality of angular frame members 2, 3, a apted to be detachably secured in rigid relation to each other in such a manner as to enable the movable or operative members of the switch mechanism to be readily assembled and supported in operative position. The angular frame member 2 is, by preference, formed of sheet metal cut and stamped to form an end frame member or plate 4, having an angular flange 5 at one extremity thereof in perpendicular relation to the main body of the plate and ada ted to be connected with a similar outer ange portion 6 of the frame member 3. (See Figs. 9 and 10).

The angular flange of the angular frame member 3 is provided with lugs 7-7 which are adapted to overlap and engage the ad- 'acent corner or margin of the frame memer 2 when said frame members 2 and 3 are together. And the angular rigidly secured of the frame member 2 is inner flange 5 provided with marginal rejections or tongues 8 which are adapte to enter and engage corres ondiiig grooves 9 in the end late or main ody portion 10 of the angular trame member 3 when the frame members 2 and 3 are in operative position. The-angular plates or frame members 2 and 3 are adapted to be separately or detachably secured in rigid relation to each other by means of screws 11, or other similar securing means, said screws being adapted to extend through apertures 12 in the outer flange 6 of the frame member 3,. and in threaded engagement with threaded openings 13 in the adjacent inner flange 5, when said flanges 5 and 6.are mounted in snugly fitting engagement with each other. The frame memers 2 and 3 are thus rigidly connected so as to form a rigid main frame formed in sections and having end plates or end frame members 4 and 10 in parallel relation to each other and spaced apart and adapted to form a suitable support for the switch-arm and the mechanism for actuating the same.

The angular frame member 2 is provided with a securing flange or base 14 which is in erpendicular relation to the end wall 4, sai flange or base 14 being provided with apertures 15 for admittin securing screws or bolts 16 for securing te frame member 2 and the attached frame member 3 in operative position upon a support, such, for instance, as a canopy or other suitable sup-y port.

A base or frame member 17 formed of fiber, an insulating composition, hard rub ber, or other suitable insulating material, secured in rigid relation to the inner me tallic frame members 2 and 3, already described, and may form one of the walls of an inclosing casing. I prefer to secure the insulatin member 17 to the flange or pla-te 6 of the inner frame member 2, and to make said insulating member or base 17 in the form of a block or plate which is adapted to form one of the walls of a box or receptacle having inner end walls 18 and side walls 19, 20 and 21, all formed of fiber, insulating composition, or other suit-able insiilating material. The receptacle or insulating lining thus formed is adapted to inclose the inner frame formed of or comprising the connected metal frame members 2 and 3, already described, and serves to cover and protect the switch mechanism supported by said connected inner frame members 2 and 3 in the insulating wall or base 17 and the insulating casing wall 21. The securing flange 14 of the inner frame member 2 is secured to the insulating inner wall 21 by means of screws 16, or other suitable securing means.

Mounted upon the insulating wall member or base 17 is a stationary metallic contact member 22, which forms one of the terminals of an electric circuit. The contact 22 is connected with a conductor wire 23 which forms part of such electric circuit and is adapted to be connected vwith one of the poles 'of a dynamo or source of electric supply. A contact 24 is also, by preference, mounted upon the insulating mem 17 and forms an opposite terminal of the electric circuit which is to-be o ned and closed by the switch mechanism erein describeds A conductor wire 25 is connected with the contact 24 and serves to connect said Contact or terminal 24 and the movable switch arm 26 with the 4opposite pole of the dynamo or source of electric power.

The movable contact member or switch arm 26 comprises in its construction an angular metallic body member 27, having'a projecting trunnion or pivot pin 28 formed thereon or integral therewith. And angular fianges 29, 29, on said metallic body member 27 are each provided with a groove 30 adapted to engage and snugly fit and support an insulating 4switch-arm member or block 31, which is formed of hard rubber, fiber, an`

insulating composition, or other similar or suitable insulating material. The insulating block 31 is adapted to engage andto be rigidly secured to and supported by the angular metal main body member 27. (See Figs. 2 to 6, inclusive, and Figs 12 and 13).

Mounted upon'and in rigid relation to the insulating member of block 31 of the movable contact member or switch arm 26 is an elongated metallic switch-arm member or finger 32, which is formed of sheet metal and provided with a sheet metal base or pivoted end comprising an angular securing flange 34, and a perforated end portion 33 in angular relation to each other, and which may be formed in one integral piece with said metal switch-arm member or finger 32. The finger or metallic arm 32 is thus adapted to be secured in rigid relation to the insulating member 31. The flange or .lug 34 is provided with an opening 37 which is adapted to register with a suitable opening 38 in the insulating body member 31; and a securing screw is anchored in the threaded opening 38 in the insulating body and extends through said opening 37 in the securing lug or flange 34, already described. The armor perforated pivoted end portion 33, which is formed u on or in one integral` piece with the metallic contact member or finger 32, is provided with an opening 39 therethrough at or near the end of said arm portion 33, arid adapted to admit a supporting pivot 40 which is anchored in or may be formed in one integral piece with' the metallic contact 24, already described.

The pivot pin 40, on the insulated base 17 or stationary contact 24 and `pivot 28 on the pivoted switch arm 26, are in alignment; and the pivot lpin or trunnion 28 is journaled er or base` vframe member 14. And

in a suitable opening 41 in the dange 14 of ,the angular inner frame member 2, already member or 'switch arm 26 in operative posi tion betweemthe stationary .contact member 24 and the metallic supporting fiange or member or finger 32 on theyswitch arm thus formed islin electrically conductive engagement with the contact 24 and pivot pin 40,

and insulated from the main metallic body member 27 kand its integral 'metallic pivot 28 on the said switch arm 26. The metallic frame members 2 and 3 and the metallic body portion 27 of the movable contact or switch arm 26 are thus effectually insulated from the contacts or stationary terminals 22 and 24; and saidstationary contacts 22 and 24 are insulated from each other by the insulating base 17, already described. The insulating base 17 is thus adapted to form a suitable support for the stationary contacts or terminals 22 and 24 and for thc metallic inner frame members 2 and 3 and the switch mechanism supported thereby.

A rotative longitudinally reciprocatory plunger 42, having radially projecting shoulders 43, 43 upon and projecting from the opposite side margins thereof and encircled by an annular sleeve or -ring 44 rigidly mounted upon and in tightly fitting engagement with and encircling the side margins of said shoulders, is mounted in the inner frame formed by the connected angular frame members 2 and 3, already described. A projecting end portion 45 oi the plunger 42 extends through a suitable opening 46 in the end plate or frame member 4, already described. and is provided with an angular end face or foot 46 which is disposed at an oblique angle with respect to the axial center of the plunger and with respect to the direction of the longitudinal movement or reciprocating movement of the plunger. The oblique end face or angular foot 46 is adapted to engage an adjacent face of the metallic body member 27 of the movable contact or switch arm 26, already described. The foot engages the pivoted switch arm 26 on opposite sides of the axis or axial center of thc switch arm, and is adapted to hold the same in circuit closing position when the plunger is in one position, and in circuit breaking position when the plunger is inverted or turned one half of a complete revolution on its longitudinal axis.

The opposite extremity or end portion 47 of the plunger 42 is rotatively mounted in the opening 48 in the end frame member or plate 10 of the sectional frame member 3, already described. (See Figs. 4 to 6,

-inclusive, and Figs. 9, 10 and 16).

A stationary cam 49, on the end plate or the metallic contact bod 4 of the frame member 2 is provided, havlng helical circumferential cam teeth 50. The cam encircles the plunger 42, and the cam teeth 50, each form a helical cam surface 51. Recesses 52 are provided between said cam teeth; and an abrupt shoulder 53 extends lengthwise of the plunger from the rojecting or extreme outer edge 54 of each lielical cam tooth 50 or cam face 51 in the direction of the switch arm engaging end of the plunger to the base of the next adjacent cam tooth. The cam teeth are thus adapted to extend between the rin or sleeve 44 and the main body of the p unger 42, and in engagement with the side shoulders 43 on the opposite sides of said plunger, so as to cause the plunger to move endwise away from the pivoted arm 26 when the plunger is rotated intermittently or 1n a step-by-step manner by means of the pull chain and ratchet. The operation of the plun er longitudinally in an opposite direction y the expansion of the spring 62 will cause the switch arm 26 to be thrown suddenly and with a snappy movement into or out of circuit-making or circuit-breakin position. (See Figs. 3 to 6, inclusive, an Figs. 10, 11 and 16).

A toothed ratchet member 56, which is, by` preference, in the form of a disk, is mounted in position to loosely encircle the plunger 42, and is provided with ratchet teeth 58, 58, which encircle the axial open- 'ing 57 in the disk or ratchet member and face toward the adjacent ends 59 of the lateral shoulders 43 on the plunger 42. Each of these ratchet teeth 58, 58, has a helical surface 60, which is adapted to slidably engage the adjacent end 59 of the adjacent laterally projecting shoulder 43 on the plunger during the intermittent movements of the ratchet member as it is operated in its backward movement into position to operatively engage the plunger.

The ratchet teeth 58 are adapted to successively engage the projecting side shoulders 43 as the ratchet is operated by meansl of its chain 71, hereinafter described.

The plunger 42 is thus intermittently rotated in one direction by means of the chain 71 and toothed ratchet 56, which will cause the cam teeth 50 of the cam 49 to engage the plunger and cause said plunger to move longitudinally out of contact with or away from the pivoted switch arm 26, already described. The plunger, upon being released by the cam teeth 56. will be snapped toward the pivoted switch arm 26 by the action of the spring 62, hereinafter described, thus causing the switch arm to be thrown into or out of circuit-making or circuit-breaking position, alternately, and with a quick movement which will prevent the formation of an arc, or the undesirable heating of or injury to the switch mechanism.

A helical spring 62 is interposed between the end plate or frame member 10 and the toothed ratchet 56 and encircles the longitudinal or elongated body portion 47 of the plunger 42. This spring is located between the ring 44 and shoulders 43 and said end plate, which forms a part of the frame member 3. One end of said sprin 62 encircles and is adapted to be supported in the proper operative osition, by means of an annular boss or s oulder 63 on the inner side of the end plate or frame portion 10 of the frame member 3. The spring is provided with a hook or bent portion 64 adapted to engage a notch 65 into which said hooked or bent end of said s ring 62 is inserted, for holding said en of the spring in operative position, so as to permit the spring to Vbe expanded or collapsed by the operation or artial rotation of the ratchet 56, attached) to the opposite end of the spring and adapted to engage and rotate the plunger intermittently or 1n a step-bystep manner.

The ratchet engaging end 66 of the s ring is provided with an angular or bent en portion 67, which extends through an opening 68 in the ratchet. And a hook 69,-formed by bending the outer projecting end portion of the sprlng which is located on the opposite side of the ratchet 56 from the main body of the spring, is adapted to admit and engage the end link 7 0 and ball 72 of a chain 71, which, by preference, comprises a series of balls or spheres 72, which are flexibly connected by the links 70. The balls 72 are of such dimensions as to readily pass through a suitable opening73 in the casing or box in which the switch mechanism to be operated is located, but are too large to pass throu h the hook 69 on the end of the spring. The c ain thus acts directly on the .hooked end of the spring to which it is attached,

A and the spring serves as a very simple and efficient means for o eratively connecting the chain with the toot ed ratchet for rotating the plunger 42. l

The switch mechanism herein shown and described is ada ted to be used in a canopy switch, or may employed for any other purpose for which electric switches are to be use In the form of the device here shown, however, the switch mechanism is mounted in a casing or receptacle formed of insulating material, as already described; and the inner receptacle of insulating material is surrounded by a box or casing 74, which may be of any desired form, material or dimensions.

The casing 74, here shown, is provided with a supporting sleeve 75, on which is mounted a threaded nut 76; and an outer threaded nut or sleeve 77 is mounted in screw-threaded engagement with the screwthreaded sleeve 75, and is adapted to engage the outer wall 7 8 of a canopy or outer casing lili through which the threaded supporting sleeve extends, said. canopy wall being interposed between the inner threaded sleeve or nut 76 and the outer threaded sleeve or nut 77. A suitable opening or bell-shaped mouth 79 is thus provided, through which the chain 71 extends. The chain 71 encircles and rests upon the sleeve or ring 44 which encircles and forms an annular peripheral portion of the plunger 42, already described. And the sleeve 44 is, by preference, of the same length as the radlal or laterally projecting shoulders 43 on the main body of the plunger 42. The end shoulders 59 and 55, therefore, flush with the corresponding ends of said sleeve.

From the foregoing, it will be readily understood by those skilled in the art, that pulling the pull chain 71 the ratchet 56 w1 l be rotated in one direction thereby causin the actuating spring 62 to be compresse and at the same time causing the plunger 42 to be partially rotated from the position in which it is shown in Fig. 4 to the relatively inverted position in which it is shown in Fig. 5. And durin such partial rotation of the plunger, -it is o vious that the shoulders or ends 55 of lateral arms 43 on the opposite sides of the plunger will be in sliding engagement with the helical cam faces 5l on the annular cam 49, thus causing the plunger to be moved endwise in a direction away from the switch arm 26, already described, or from the position in which said plunger is shown in Fig. 4 to the position in which it is shown in Fig. 5. It is also plain that the further rotation of the plunger very slightly in the direction in whlch it is rotated bj, means of the pulling of the chain 71 will germit the plunger to be released from contact with the helical cam faces of the cam 49, and the plunger will thus be snapped forward or endwise in the direction of the switch arm 26 by the action of the spring 62, as it expands upon the instant when the plunger is thus released, thus causing the plunger 42 and switch arm 26 to be moved from circuit breaking position, as shown in Fig. 5, to circuit closing position, as shown in Fig. 6.

rlhe switch arm 26 is provided with a helical compression spring 80 which is interposed between the metallic body 27 of said switch arm and the adjacent stationary flange 14 of frame member 2 already described. 'lhis spring 80 encircles the pivot 28 and serves to yieldingly press and hold the pivoted switch arm in yielding frictional engagement with the supporting pivot 40 and contact or switch arm support 24, at all times, and also with the contact 22 when the switch is in circuit closing position. The yieldingly frictional engagement thus afforded by the spring 8O is suiiicient to hold the to operatively engage and rotate the plunger 42 intermittently or in a step-by-step manner.

l claim:

1. In an electric switch, the combination of a contact adapted to be electrically connected with a source of electric supply, a movable contact member adapted to be moved into and out of engagement with said first-mentioned contact, an electric conductor embraced within the same electric circuit with said first-mentioned contact and adapted to form an electric connection between Saul movable contact member and the source of elect-ric supply, and a rotative reciprocatory actuating member adapted to actuate said movable contact member and forming a movable stop adapted to stop the latter 1n a position into which the same is adapted to be moved by said rotative reciprocatory actuating member.

2. In an electric switch, the combination of a contact adapted to be electrically connected with a source of electric supply, a movable contact member adapted to be moved into and out of engagement with said first-mentioned contact, an electric conductor embraced within the same electric eircuit with said first-mentioned contact and adapted to form an electric connection be tween said movable contact member and the source of electric supply, a rotative reciprocatory actuating member adapted to actuate said movable contact member and forming a stop for stopping the latter in circuitclosing and circuit-breaking positions respectively, and means for reciprocating and intermittently rotating said rotative reciprocatory actuating member.

3. ln an electric switch, the combination of a Contact adapted to be electrically connected with a source of electric supply, a movable contact member adapted to be moved into and out of engagement with said first-mentioned contact, an electric conductor embraced within the saine electric circuit with said first-mentioned contact and adapted to form an electric connection between said movable contact member and the source of electric supply, a rotative reciprocatory actuating plunger adapted to actuate said movable contact member, and provided with a stop movable with said plunger and adapted to stop said movable conlill-l tact member in a position .into which Athe latter is adapted to be moved by sa1d plunger.

4;. n an electric switch, the combination of a contact member adapted to be electrically connected with a source of electric supply, a pivoted contact member adapted to be moved into and out of operatlve engagement withy said first-mentioned contact, an electric conductor embraced within the same electric circuit with said firstmentioned contact and adapted to form an electric connection between said movable contact member and the source of electric supply, a rotative reciprocatory actuating plunger adapted to enga e and move the pivoted contact member 1nto and out of circuit-closing osition, and acting to positively stop sai plivoted contact member in a position into w ich the same is adapted to y' be moved by said plunger, resilient,v means for actuating said plunger in-one direc-l tion of its reclprocatory movement, and

means for intermittently rotating and actuating said plunger .in an opposite direction of its reciprocatory movement.

. 5. In an electric switch, the combination of a contact member adapted t0 be connected with av source of electric supply, a reciprocatory contact bar `movab e into and out of engagement with said first-mentioned contact and ada ted to be electrically connectedv with a con uctor and source of electric supply embraced wi'thin the same electric circuit with said firstmentioned contact member, a rotative reciprocatory actuating plunger havingan end margin adapted to actuate and form a movable stop for positively stopping said reciprocatory. contact bar in a position into which the latter is adapted to be moved by said plunger, a laterally projecting shoulder on said plunger, cam and ratchet mechanism encircling said plunger and adapted to operatively engage said lateral projection, said ratchet mechanism acting to intermittently rotate said plunger upon its axis and with resepct to sa1d cam, and resilient means tending to actuate said plunger longitudinally in one direction independently of said cam.

6. In an electric switch, the combination of a contact adapted to be electrically connected with a source of electric supply, a movable 'contact member connected with the source of electric supply and adapted to be moved into and out of engagement with said first lmentioned contact, a rotative reciprocatory actuating member adapted to operatively engage said movable contact member, a spring operatively connected with said ro tative reciprocatory actuating member for actuating the same' in one direction of its reciprocatory movement, and a ratchet member in operative engagement with said rotative reci rocatory actuating member, and `o erative y connected with and adapted to e operated in one direction by said sprinlg. v l

7 n an electric switch, the combination of a contact adapted to be electrically con nected with a source of electric su ply, a movable -contact member adapted tohe connected with said source of electric supply and movable into and out\of engagement with said first mentioned contact, a rotative reciprocatory actuating lunger adapted to operatively engage said movable con- \ta.ct member, resilient means for actuating sa1d plunger in one direction of its reciprocatory movement, means for operating said plunger 1n an opposite direction to that m. w lch it is moved by the resilient actuatin means, `and a reciprocatory ratchet mem r in operative engagement with said plunger and operativel connected with and adapted to be operate in one direction by sai resilient actuating means.

8. In an electric swltch, the combination of a stationary contact adapted to be electrically connected with a source of electric supply, a movable contact member adapted to be connected with said source of electric supply and movable into and out of engagement with said rst mentioned contact, `a rotative reciprocatory actuating plunger adapted to operatively engage said movable contact member, a cam in operative engagement with said reciprocator plunger and ada ted to tend to press sa1d plunger longitudinally in one 'direction a spring adapte, to actuate the plunger longitudinally in an opposite direction, and a ratchet member in operative en agement with the plunger and adapted to a actuated intermittently in one direction by said spring.

9. In an electric switch, the combination of a stationary contact, a. switch arm movable into and out of engagement with said contact, means for connecting said contact and said/ switch arm,'respectively, with a source of electric supply, a rotative reciprocatory actuating plunger adapted to operatively engage said movable switch arm, a cam in operative engagement with the plunger and adapted to tend to press the same endwise in one direction of its reciprocatory movement, a spring adapted to actuate said rotative reciprocatory plunger endwise in an opposite direction, a ratchet member in operative engagement with the lunger and operatively connected with and) be actuated intermittently in one direction bysaid sprin ,and means for operating said ratchet mem r in an opposite direction, to actuate the plunger.

10. In an electric switch, the combination of a stationary contact, a ivoted switch arm movable into and out o .engagement with adapted to Gill) said contact, means for connecting said contact and said switch arm, respectively, with a source of electric supply, a cam having a helical cam surface in operative engagement with the plunger and adapted to tend to press the plunger in a direction away from said pivoted switch arm, a spring adapted to actuate said plunger 1n an opposite direction toward the pivoted switch arm, a ratchet member interposed between said spring and said switch arm and in operative engagement with the plunger, and adapted to ,be actuated in one direction automatically, and means for operating said ratchet in an opposite direction to intermittently actuate and release the plunger,

11. ln an electric switch, the combination of a contact adapted to be electrically connected with a source of electric supply, a switch arm movable into and out of engagement with said first mentioned contact and adapted to be electrically connected with said source of electric supply, a rotative reciprocatory actuating plunger havingk one end adjacent to and rovided with an end face disposed oblique y with respect to the direction of movement of the plunger and adapted to engage said movable switch arm, a projecting s oulder on said plunger, a cam encircling the plunger and having a helical cam face adapted to engage said projecting shoulder during the partial rotation of the plunger and adapted to permit longitudinal movement ot the plunger in the direction of the movable switch arm, a plunger actuating spring encircling the plunger and adapted to actuate the same in the direction of sald movable switch arm, and a toothed ratchet member mounted in operative engagement with a shoulder portion of said plunger and operatively connected with and adapted to be operated in one direction by Said plunger actuating spring.

12. lln an electric switch, the combination of a stationary contact, a movable switch arm adapted to be moved into and out of engagement with said contact, means for connecting each of said elements with an electricy circuit, a rotative reciprocatory actuating plunger adapted to operatively engage said switch arm, a cam in engagement with said reciprocatory plunger, and adapted to tend to press said plunger endwise in one direction, a ratchet in engagement with the plunger, a spring in engagement with and adapted to actuate the ratchet in one directionand a Hexible element directly connected with said spring and acting to intermittently actuate the ratchet in an opposite direct1on against the tension of the spring, to intermittently actuate the pluner. g 13. ln a electric switch, the combination of a stationary contact, a movable switch arm adapted to be moved into and out of engagement with said contact, means for connecting each of said elements with an electric circuit, a rotative reciprocatory actuating plunger adapted to operatively engage said switch arm, a cam in engagement with and adapted to tend to press said plunger endwise in one direction, and plunger actuating means comprising a ratchet 1n engagement with the plunger, a spring in engagement with and adapted to actuate the ratchet in one direction, 'said spring being also adapted to actuate said plunger endwise in the direction of said movable switch arm and a exible element directly connected with said spring and' acting to actuate the ratchet in an opposite direction against the tension of the spring, to intermittently actuate the plunger.

la. ln an electric switch, the combination oim a stationary contact, a movable switch arm adapted to be moved into and out of engagement with said contact, means for connecting each of said elements with an electric circuit, a rotative reciprocatory actuating plunger adapted to operatively engage said switch arm, and plunger-actuating means comprising a cam in operative engagement with the plunger and adapted to tend to move said plunger endwise in one direction intermittently, a ratchet in' engagement with the plunger, a spring having one end attached to said ratchet, and a chain connected with said ratchet-engaging end of said spring and adapted to actuate the ratchet intermittently against the tension of the spring, to actuate the plunger.

l5. lin an electric switch, the combination of a stationary contact, a movable switch arm adapted to be moved into and out of engagement with said contact, means for connecting each or said elements with an electric circuit, a rotative reciprocatory actuating plunger adapted to operatively engage said switch arm, and plunger-actuating means comprising a cam in operative engagement with the plunger and adapted to tend to move said plunger endwise in one direction intermittently, a ratchet in engagement with the plunger, a spring adapted to actuate said plunger intermittently in an opposite direction with respect to said cam and having one end connected with said ratchet, and an operating chain detachably connected with said ratchet-engaging end of said spring and adaptedg, to actuate the ratchet intermittently against the tension of the spring, to actuate and release the' plunger.

lrlln an electric switch, the combination of a stationary contact, a movable switch arm adapted to be moved into and out oi engagement with said contact, each of said elements being adapted to be connected with an electric circuit, insulating supporting means for said contact and said switch arm,

tti

lll

`an electric circuit, insulatin a rotative reciprocatory actuating' plunger having an end ortion adapted to en ge said movable switch arm, an annular s eeve fixed to and encircling the main body of' sleeve and adapted to actuate the ratchet in-4 termittently against the tension of the spring, to actuate said plunger.

17. In an electric switch, the combination of a stationary contact, a movable switch arm adapted to be moved into and out of engagement with said contact, each of said elements being adapted to be connected with supporting means for said contact and sai .switch arm, a rotative reciprocatory actuating plunger having an said movable switch arm, lateral prolections on the main body of said plun r, a ring fixed to and encircling said latera projections, and plunger-actuating means comprising a cam in operative engagement with said lateral projections and adapted to -tend to press said plunger endwise in one direction intermittently, n the opposite side of said ring from said cam and adapted to operatively engage the plunger, a spring encircling the plunger and in engagement with the ratchet, said spring being adapted to actuate the plungerendwise intermittently in an opposite direction with respect to the cam, and a exible operating member operatively connected with said ratchet and spring and adapted to actuate the ratchet intermittently against the tension of the spring, to actuate and release the plunger. l

18. In an electric switch, the combination of a contact, a movable switch arm adapted to be moved into and out of engagement with said contact, means for connecting said contact and said switch arm with a source of electric supply, insulating supporting means for said contact and switch arm, a rotative reciprocatory actuating plunger adapted to operatively engage said movable contact member, and plunger-actuating means comprising a cam in operative engagement with said rotative reciprocatory lunger and adapted to tend to move'said p u ngerD endwise longitudinally in one direction intermittently, a spring operatively connected with said plunger and adapted to operate the same endwise in an opposite direction, a plunger-operating ratchet member in operaand adapted to tend'toA end portion adapted to engagel a ratchet mounted' on' tive engagement with the plunger and adapted to be actuated intermittent y in one direction by said spring, and means for actuating the ratchet member in an opposite direction against the tension of said spring, to intermittently rotate the plunger and cause the same to move endwise during such intermittent\rotative movements. g

19. In an electric switch, the combination of 'a plurality of stationary terminals each adapted to be connected with a source of electric supply, a .pivoted switch arm in contact with one of said stationary terminals and movable into and out 0f engagement with the other one of said terminals, a rotative reciprocatory actuating plunger adapted to operatively engage said pivoted switch arm, and plunger-actuating means comprising a spring adapted to actuate the plunger endwise in one direction toward the switch arm, and cam and ratchet mechanism in operative engagement with and adapted to actuate the plunger endwise in a direction away from the switch arm, and acting to turn said plunger on its axis intermittently, in a step-by-sep manner into position to be actuated by said spring.

20. In an electric switch, the combination of a plurality of stationary terminals each adapted 'to be connected with a source of electric supply, a pivoted switch arm in contact with one of said stationary terminals and movable into and out of engagement with the other one-of said terminals, a rotative reciprocatory actuating plunger adapted to operatively engage said pivoted switch arm, and plunger-actuating means comprising a cam in operative engagement with said rotative reciprocatory plunger and adapted to co-act with plunger-operating ratchet mechanism to actuate said plunger in one direction of its reciprocatory movement, a spring adapted to operate the plunger in an opposite direction, a plungeroperating ratchet' in operative engagement with the plunger and adapted to be actuated intermittently in one direction automatically, and means for actuating the ratchet member in an opposite direction to actuate the plunger in the direction of the pivoted switch arm.

21. Inan electric switch, the combination of aplurality of stationary terminals each adapted to be connected with a source of electric supply,apivoted switch arm in contact with one and movable into and out of engagement with the other one of said terminals, a rotative reciprocatory actuating plunger adapted to operatively engage said pivoted switch arm, and plunger-actuating means comprising a cam in operative engagement with said rotative reciprocatory plungerand adapted to tend to move said plunger in one direction of its reciprocatory movement, a spring adapted to operate the mams@ 9 plunger in an opposite direction a plungerv Si :f at Chica v in the eolmty of Cook operating ratchet in o erative engagemem; and nte of Dinothis 22nd day of June, m with the plunger and, a ted to be actuated 1922. intermittently in one 'retion by said i5 spring, .and means for actuating the ratchet; -WHLI LINDSAY' member in an opposite-direction to actuaie Witnesses: the plunger in the direction of the 1M; i HARRY I. CBO switch erm. JENNm L. Frsxn. 

